Abstract:

The invention concerns an arrangement for the joining and attachment of a
wear lining element (1) onto a surface that is subject to wear, a
supporting surface (5) of a supporting construction (2), comprising
attachment means (9) that when anchored in the wear lining element are
each one intended to be inserted into attachment holes (10) arranged in
the supporting construction whereby the wear lining element is held
fastened against the supporting surface by means of supplementary
fastening means (16) that are associated with the attachment means
positioned to interact with the tensioning surface (11) located on the
opposite side of the supporting surface. For rapid and safe fixing, the
attachment means (9) comprises a holder (13) fixed attached to the wear
lining element (1), a guide (14) designed to guide the wear lining
element into place against the supporting surface through interaction
with a hole wall in the attachment holes (10) of the supporting
construction, a mounting (15) designed to hold the wear lining element
fastened against the supporting surface (5) through interaction with the
tensioning surface (11) of the supporting construction and fixing and
locking means (12) that allow the guide and the mounting to be held in
place in a manner that allows exchange, supported by the holder. The
invention concerns also a wear lining element intended to be mounted on
the inner surface of a rotary grinding drum.

Claims:

1. An arrangement for the attachment of a wear lining element (1) onto a
surface that is exposed to wear, a supporting surface (5) of a supporting
construction (2), comprising attachment means (9) that when anchored in
the wear lining element are each one intended to be inserted into
attachment holes (10) arranged in the supporting construction whereby the
wear lining element is fastened against the supporting surface by means
of supplementary fastening means (16) that are associated with the
attachment means and positioned to interact with what is known as the
tensioning surface (11) located on the opposite side of the supporting
surface, characterised in that the attachment means (9) comprises a
holder (13) fixed attached to the wear lining element (1), a guide (14)
designed to guide the wear lining element into place against the
supporting surface through interaction with a hole wall in the attachment
holes (10) of the supporting construction, a mounting (15) designed to
hold the wear lining element fastened against the supporting surface (5)
through interaction with the tensioning surface (11) of the supporting
construction, and fixing and locking means (12) that allow the guide and
the mounting, respectively, to be held in place in a manner that allows
exchange, supported by the holder.

2. The arrangement according to claim 1, comprising temporary locking
means (28) that make it possible to temporarily lock the wear lining
element (1) against the supporting surface (5) of the supporting
construction (2) through interaction between the guide (14) and the
tensioning surface (11) of the supporting construction.

3. The arrangement according to claim 2, whereby the temporary locking
means (28) comprises a first locking member (29) and a second locking
member (30) that act together, the said second locking member of which
being arranged at the guide (14).

4. The arrangement according to claim 3, whereby the first locking member
(29) can be introduced into the second locking member (30) and the
locking members are held fixed in the united condition through the
influence of a snap device (31) that acts between the members.

5. The arrangement according to claim 1, whereby the fixing and locking
means (12) allows both the guide (14) and the mounting (15) to be united
with the holder (13) in a manner that allows them to be removed.

6. The arrangement according to claim 1, comprising means (21) that can be
accessed from the tensioning surface (11) after they have been united
with the attachment holes (10) and that allow the guide (14) to be
released and removed from the holder (13).

7. The arrangement according to claim 1, whereby the fixing and locking
means (12) with which the guide (14) and the mounting (15) are united
with the holder (13) in a manner that allows them to be freed comprise a
threaded joint that acts between the respective parts.

8. The arrangement according to claim 6, whereby the means (21) for the
release and removal of the guide (14) from the holder (13) comprises a
turning means arranged at the guide designed for interaction with a
turning tool.

9. The arrangement according to claim 8, whereby the turning means (21)
comprises grips (22) arranged at the free end of the guide (14) and of
the mounting (15) designed for interaction with a wrench key.

10. The arrangement according to claim 1, whereby the mounting (15)
comprises a fixing sheath (17) provided with an internal thread that
protrudes from the wear lining element (1).

11. The arrangement according to claim 1, whereby the guide (14) is
extended and comprises an element having the form of a peg that
demonstrates a part (19) that has the form of a stud that is circular and
is provided with an external thread that can be united with the holder
(13) by screwing and a circularly cylindrical part (20) that has the form
of a peg that narrows in a conical manner towards its free end.

12. The arrangement according to claim 9, whereby the turning means (21)
of the guide (14) is arranged at the free end of the part (20) that has
the form of a peg.

13. The arrangement according to claim 1, whereby the mounting (15)
comprises a screw means (23) with the form of a stud that can be screwed
into the holder (13).

14. The arrangement according to claim 1, whereby the mounting (15)
comprises a turning means (24) that allows the mounting to be released
from the holder (13).

15. The arrangement according to claim 14, whereby the turning means (24)
of the mounting (15) is arranged at the free end of the mounting.

16. A wear lining element intended to be mounted on the inner surface of a
rotary grinding drum, characterised in that it comprises an arrangement
for the uniting and fixing of the type that is specified in claim 1.

17. The wear lining element according to claim 16, comprising a bottom (3)
of sheet metal with a convex form with a curvature that corresponds to
the concave inner surface of the rotary grinding drum, and an upper
surface (4) of a wear-resistant material with an irregular form.

18. The wear lining element according to claim 17, whereby the
wear-resistant material comprises rubber or an elastomeric material and
is united with the bottom (3) through vulcanisation.

19. The wear lining element according to claim 18, whereby the upper
surface (4) has the form of two ridges (6) that are separated by a
distance and run parallel to each other and that protrude in towards the
centre of the drum, and a part (7) that has the form of a valley and lies
at a significantly lower height situated between the two ridges, and in
which part having the form of a valley lifting hooks (8) are arranged
intended for interaction with a hook or similar lifting means that is a
component of a lifting accessory.

Description:

[0001]The present invention concerns an arrangement for the attachment of
a wear lining element onto a surface that is exposed to wear in a
supporting construction according to the introduction to claim 1. The
invention concerns also a wear lining element for a rotary grinding drum
according to the introduction to claim 16

[0002]Wall sections that are part of, for example, rotary grinding drums,
chutes, channels and similar constructions are subject to wear, and are
for this reason provided on their surface that is exposed to wear with a
wear lining of wear-resistant material in order to increase the ability
of the wall to withstand wear, abrasion, impacts and blows. This wear
lining material is normally constituted by an elastomeric material, but
it may also consist of other suitable materials with high resistance to
wear, such as highly alloyed steel. A wear lining is normally divided
into smaller units, known as segments, in the form of wear lining
elements that in order to form a cladding are brought into contact next
to each other on the side of the supporting construction that is exposed
to wear. The wear lining elements are fastened to the support with the
aid of fixing screws or bolts that are inserted into special attachment
holes arranged in the supporting construction.

[0003]Since the wear lining elements are normally brought into contact
with the side of the wall or the supporting construction that is exposed
to wear while it is mounted using the said attachment holes from the
opposite side of the supporting construction, known as the tensioning
side, there are major problems associated with adapting each individual
wear lining element such that the attachment means are located in the
centre of each attachment hole before the wear lining element can be
lowered into place.

[0004]Since the wear lining elements are relatively heavy, lifting aids,
such as the arm of a crane or similar, are required. When installing
lining into a rotary grinding drum for which the wear lining elements
need to be replaced at relatively frequent intervals, the wear lining
elements are lifted into the drum from one end and placed into position
inside the drum, on its inner surface. Even if the crane operator is
skilled, the actual adaptation of the wear lining elements to the inner
surface of the drum is work that is both dangerous and time-consuming.

[0005]As has been mentioned above, one of the problems that are most
difficult to solve when using wear lining elements as wear protection, is
the technology for the rapid and efficient placement and fastening of the
wear lining elements in question onto the supporting construction
surface, i.e. onto the surface that is to be protected from wear. The
known methods that have been suggested include providing the wear lining
element with attachment holes such that a certain part of the mounting
operation can take place from the side of the wear fining element that
faces outwards, and making it possible to adapt the wear lining element
such that the relevant attachment holes of the wear lining element and
those of the supporting construction are located immediately above each
other. In the said position, i.e. when the two holes are located
immediately above each other, attachment means are introduced from the
side of the wear lining element that is exposed to wear, i.e. from the
wear side, in through the two holes such that it becomes possible to
access the attachment means from the lower surface of the supporting
construction, or more accurately, from the tensioning side of this
surface. Such arrangements are known from, for example, U.S. Pat. No.
6,036,127 and U.S. Pat. No. 6,082,646. The disadvantage of this prior art
technology is that the wear of the wear lining elements increases due to
the cavities that are formed. In particular, wear increases in those
zones of the wear lining element that demonstrate holes. The lifetime of
the wear lining elements can be increased by avoiding holes in the
surface exposed to wear.

[0006]One of the problems that is difficult to master when using wear
lining elements, in addition to that of the alignment during attachment,
is that of achieving wear lining elements with as low an amount as
possible of metallic material, without compromising on the requirement
that it is to be possible to attach the elements in question rapidly and
securely onto the supporting construction, i.e. the surface that is to be
protected from wear.

[0007]One aim of the present invention, therefore, is to achieve an
arrangement for the attachment of wear linings and wear lining elements
onto the side of a supporting construction that is exposed to wear such
as, for example, the wall or inner surface of a rotary grinding drum,
which attachment arrangement leads to improved use and greater freedom
during the construction and design of the rubber part, together with
rapid and safe attachment of the wear lining elements onto the supporting
construction. A further aim of the present invention is to achieve a wear
lining element for a rotary grinding drum.

[0008]The aim of the invention is achieved with the aid of an arrangement
that demonstrates the properties and characteristics that are specified
in claim 1, and with the aid of a wear lining element of the type
specified in claim 16.

[0009]Further characteristics and advantages of the invention are made
clear by the non-independent claims.

[0010]An embodiment of the invention will be described below with
reference to the attached drawings, of which:

[0011]FIGS. 1-2 show a view in perspective of a wear lining element
equipped with an attachment arrangement according to the present
invention, which wear lining element is viewed obliquely from above and
obliquely from below, respectively;

[0012]FIGS. 3-7 show cross-sections through the wear lining element shown
in FIG. 1 in the form of steps under the anchoring to a surface of a
supporting construction exposed to wear, which supporting construction
herewith is constituted by the drum wall of a grinding mill;

[0013]FIG. 8 shows a view in perspective of a guide that is a component of
the attachment arrangement;

[0014]FIG. 9 shows a view in perspective of a mounting that is a component
of the attachment arrangement.

[0015]An extended wear lining element of the type that is intended to be
placed in a row one after the other in order to form a cladding on the
inside of a supporting construction generally denoted by 2 is shown in
FIGS. 1 and 2, generally denoted by 1. The said supporting construction
is shown in more detail in FIGS. 3-7 and it is constituted in this case
by the wall of a rotary grinding drum that is exposed to wear. The wear
lining element 1 has a bottom 3 that consists of a reinforcement of metal
with wear protection in the form of an upper surface 4 of an elastic or
rubber material such as, for example, natural rubber or synthetic rubber
such as polyurethane. The wear protection is, naturally, not limited to
elastomeric material: it can be constituted by any material that is
suitable for the purpose. It may be constituted also by a durable
metallic material.

[0016]As is made most clear by FIGS. 3-7, the wear lining element 1 is
adapted in form to the supporting construction and it demonstrates a
bottom 3 that is convex, with a curvature that corresponds to the concave
supporting surface 5 of the supporting construction 2. The upper surface
4 of the wear lining element 1 has an irregular shape and is of rubber or
an elastomeric material. It is joined to the bottom 3 through
vulcanisation, although it would be possible also to attach it by another
method, such as gluing.

[0017]In order to agitate the charge of ore in the rotary grinding drum
the upper surface 4 forms ridges 6 that extend axially along the rotary
grinding drum and that protrude in towards the centre of the drum.
Lifting loops 8 are arranged on the said upper surface 4 in a valley part
7 that is located at a significantly lower height between two parallel
ridges 6, which lifting loops are intended to interact with a hook or
similar lifting means that is a component of a lifting accessory such as
a crane, with the purpose of facilitating the handling of the wear lining
element 1, principally due to the good balance that is obtained in this
way. Attachment means 9 are arranged at the bottom of the wear lining
element 1 intended for mounting of the wear lining element onto the
supporting surface 5 of the supporting construction following
introduction of the attachment means into attachment holes 10 arranged in
the supporting construction 2. When the said attachment means 9 has been
inserted into the attachment hole and extends out from the opposite side
of the attachment hole 10, i.e. the side that faces away from the
supporting surface 5 of the supporting construction 2 and forms a
tensioning surface, the wear lining element 1 can be fastened onto the
supporting surface 5 through the attachment means being brought into
interaction with the tensioning surface through a fastening means that is
a part of the attachment means. The said fastening means may be
constituted by, for example, a nut and its associated washer.

[0018]FIGS. 3-7 show a series of cross-sections through the said wear
lining element 1 and the supporting construction 2 during the insertion
of the wear lining element and its mounting onto the supporting surface 5
of the supporting construction 2. The drawings make it clear that the
concave supporting surface 5 of the supporting construction 2 is formed
by sheet metal reinforcement and a ring-shaped cladding of elastomeric
material laid onto this sheet metal. The said cladding is attached to the
sheet metal by vulcanisation and forms the above-mentioned tensioning
surface 11, which in this case is convex. The attachment means, generally
denoted by 9, of the wear lining element protrudes from the convex bottom
3 of the wear lining element and it is, as has been described above,
intended to be inserted into attachment holes 10 in the supporting
construction 2.

[0019]Each attachment means 9 comprises, according to the invention, a
number of parts that can be united by interacting fixing and locking
means 12, which parts are principally constituted by a holder 13 that is
fixed attached to the wear lining element and that protrudes from the
bottom 3 of the wear lining element, and two parts that can be united
with the holder in a manner that allows them to be removed intended to be
supported by the holder in a retentive manner. One of these two unitable
parts forms a guide 14 for the insertion or direction of the wear lining
element towards the supporting surface 5 of the supporting construction 2
through interaction with the attachment holes 10 of the supporting
construction 2. The second of these unitable parts forms a mounting 15 in
order to fix and hold in place by pressure the wear lining element 1
against the supporting surface 5 of the supporting construction 2 through
interaction with the tensioning surface 11 of the supporting construction
2. The guide 14 and the mounting 15 are shown in more detail in FIGS. 8
and 9. In the embodiment described here, the mounting comprises a
supplementary means 16 of fastening that can be adjusted for interaction
with the tensioning surface 11 of the supporting construction 2.

[0020]FIGS. 3-5 make it clear that the holder 13 comprises an attachment
sheath 17, the fixing and locking means 12 of which are constituted by an
internal thread and a flange part 18 that has a relatively large
diameter, to which flange the attachment sheath is attached by welding at
the bottom 3 of the wear lining element 1 with the attachment sheath
protruding from the bottom of the wear lining element.

[0021]FIG. 8 makes it clear that the guide 14 comprises an element having
the form of a peg, the fixing and locking means of which are constituted
by a stud-shaped section 19 with circular cross-section, which
stud-shaped section is provided with an external thread and can be united
by screwing with the holder 13 and with a part 20 that is circularly
cylindrical and has the form of a peg, which part 20 narrows towards its
free end in a conical manner and whose cylindrical diameter exceeds the
diameter of the stud-shaped part 19. FIG. 3 makes it clear that the
attachment sheath 17 of the holder 13 and the circularly cylindrical part
of the guide 14 have been given corresponding outer diameters. The part
20 that has the form of a peg has been given the dimensions required to
ensure that it acts as guidance towards the holed wall with the
attachment holes 10 of the supporting construction 2 during adaptation of
the wear lining element 1 to the supporting surface 5 of the supporting
construction 2. The guide 14 is provided at its free end with a means 21
that has been designed for rotation and that can be accessed such that
the guide can be placed into and removed from locking interaction with
the holder 13. This turning means 21 comprises a grip 22 arranged at the
free end of the part 20 that has the form of a peg, designed for
interaction with a turning tool. Since the turning means 21 is arranged
at the free end of the guide 14, it is possible, as FIG. 4 makes most
clear, to access the turning means also for the loosening and removal of
the guide 14 from the holder 13 when the guide is located in the
attachment hole 10.

[0022]With reference also to FIG. 9, the mounting 15 comprises fixing and
locking means 12 designed as a stud bolt 23 by which it is possible to
screw the mounting into the holder 13. It is possible to access also the
mounting 15 with the aid of a turning means 24 in order to place the
guide into and remove the guide from locking interaction with the holder
13. The said turning means 24 comprises a grip 25 arranged at the free
end of the mounting 15, intended for interaction with a turning tool and
for attachment of the mounting 15 in the holder 13 and for removal of the
same from the holder through the interacting threads of the two parts.
The fastening means 16 that is associated with the mounting 15 is shown
in more detail in FIG. 7 and it comprises a nut 26 that interacts with
the stud bolt 23 and a washer 27 that is intended to be placed between
the said nut and the tensioning surface 11 of the supporting construction
2. Also a rubber washer is arranged between the washer 27 and the
tensioning surface 11. It should be understood that the wear lining
element 1 is pressed against the supporting surface 5 of the supporting
construction 2 when the nut 26 is tightened against the tensioning
surface 11 of the supporting construction 2.

[0023]FIG. 4 and the enlarged details shown with dot-dashed lines make it
clear that the present attachment arrangements comprise a locking means
generally denoted by 28 that makes possible rapid and temporary
attachment of the wear lining element 1 onto the supporting surface 5 of
the supporting construction 2. The opportunity for rapid temporary
attachment of the wear lining element is particularly interesting in
certain applications since it contributes to shortening the assembly
period. Not least for the exchange of drum linings in grinding mills is
this important, since it reduces the requirement for dangerous operations
inside the grinding drum itself while the final mounting operation can be
carried out externally and from the tensioning side of the rotary
grinding drum as a subsequent operation at a suitable later time. Such a
suitable later time is immediately before the mill is to be taken into
operation.

[0024]In a first alternative embodiment, the temporary locking means 28
can comprise a first lock member 29 in the form of a U-shaped element and
a second lock member 30 in the form of a hole in the guide 14 that
corresponds to one of the legs or shanks of the U-shaped element. FIG. 4
makes it clear that the leg of the first lock member 29 is intended to be
inserted into the said hole for temporary locking of the wear lining
element 1 onto the supporting surface 5 of the supporting construction 2
through interaction between the guide 14 and the temporary locking means
against the tensioning surface 11 of the supporting construction. The
locking member 29 enters into locked, or self-limiting, interaction with
the second lock member 30 through the influence of a snap fastener 31 in
the form of a spring metal plate that is a component of the lock member
28.

[0025]As is shown in the enlargement of details in FIG. 4, the first lock
member 29 can in a second alternative embodiment comprise a wedge
designed to interact with a second lock member 30 in the form of a hole
arranged in the guide peg with a form that corresponds to that of the
wedge.

[0026]The first lock member 29 can in a third alternative embodiment
comprise a key that has been given U-shaped forked shanks at one of its
ends, which shanks are to engage with the guide 14 in a manner that
provides locking through surrounding at an angle greater than 180°
a sector of a circle of a circumferential track arranged in the guide.
This means that the forked shanks are sprung shanks, and have such a
length that they snap onto the said circumferential track.

[0027]FIGS. 3 and 4 make it clear that the present lock arrangement acts
in the following manner: After engagement of the guide 14 into the holder
13 with the aid of a suitable turning tool in interaction with the grip
22, the wear lining element 1 is introduced and guided down in towards
the concave supporting surface 5 of the supporting construction 2 through
interaction between the guide 14 and the holed wall of the attachment
holes 10 of the supporting construction. With the wear lining element 1
in place, the wear lining element 1 can be temporarily fixed onto the
concave supporting surface 5 of the supporting construction 2 by means of
the locking means 28 and in that the locking members 29, 30 are brought
into positions at which they interact.

[0028]FIGS. 5-7 make it clear that following loosening and removal of the
guide 14 that has been inserted into the attachment hole 10 from the
holder 13 of the wear lining element 1 by means of a suitable tool in
interaction with the grip 22, the mounting 15 is attached in the holder
13, an operation that is carried out by means of a turning tool in
interaction with the grip 25 of the mounting, and screwing the mounting
into the holder. Finally, the wear lining element 1 is fastened against
the concave supporting surface 5 of the supporting construction 2 through
the fastening means 16, in the form of nut 26 and washer 27 and sealing
washer, that is associated with the mounting 15 being tightened by means
of a suitable turning tool onto the tensioning surface 11 of the
supporting construction 2.

[0029]The present arrangement is not limited to that which has been
described above and shown in the drawings: it can be changed and modified
in a number of different ways within the framework of the innovative
concept specified by the attached patent claims. It should be understood,
for example, that it would be possible to replace the mounting 15 and its
associated fastening means 16 by a suitable screw or bolt provided with a
casing.